const puppeteer = require('puppeteer')
const fs = require('fs');
const superagent = require('superagent');
const path = require('path');

var url = '';
process.argv.forEach((val, index, array) => {
    console.log(val)
    if(val.startsWith('url=')){
        url = val.substring(4);
    }

})
if(!url || url.length === 0) {
    console.log('Need to supply url');
    process.exit();
}


const processors = [{
  baseUrl: 'bringatrailer.com',
  pageLoadIndicator: '.gallery',
  vinSelector: 'body > main > div.listing > div:nth-child(3) > div.column.column-right.column-right-force > div.essentials > div:nth-child(5) > ul > li:nth-child(1) > a',
  carouselTrigger:  '.gallery > a:nth-child(1)'

}, {
  baseUrl: 'classiccars.com',
  pageLoadIndicator: '#ListingCarousel',
  vinSelector: 'li.p-vin > span:nth-child(2)',
  carouselTrigger: 'div.swiper-slide-active > div > img.u-photo'
}]
var processorConfig = {}
processors.forEach(config => {
  if(url.includes(config.baseUrl)){
    processorConfig = config;
  }
})
if(!processorConfig) {
  console.log('Unsupported URL');
  process.exit();
}

const run = async () => {
    const browser = await puppeteer.launch({
        headless:true
    });
    
    const page = await browser.newPage();
  
    await page.goto(url);
    
    // Type into search box.
    // await page.type('.devsite-search-field', 'Headless Chrome');
  
    // Wait for suggest overlay to appear and click "show all results".
    const allResultsSelector = processorConfig.pageLoadIndicator;
    await page.waitForSelector(allResultsSelector);


    const vinSelector = processorConfig.vinSelector;
    await page.waitForSelector(vinSelector);
    let element = await page.$(vinSelector)
    let vin = await page.evaluate(el => el.textContent, element);
    console.log(vin);
    // await page.click(allResultsSelector);

    const client = await page.target().createCDPSession()
    await client.send('Page.setDownloadBehavior', {
    behavior: 'allow',
    downloadPath: './images',
    })
    const firstImageLinkSelector = processorConfig.carouselTrigger;
    await page.click(firstImageLinkSelector);
    await page.waitForSelector('.pswp__img')
    console.log('Gallery is loaded, fetching URLS')
    const galleryUrls = await page.evaluate(downloadGallery, vin);
    console.log('Done collecting URLS', galleryUrls.length);
    await Promise.all(galleryUrls.map(image => new Promise(async (resolve, reject) => {
      const fileType = path.extname(image.url);
      var stream = fs.createWriteStream(path.resolve('images', `${image.fileName}${fileType}`));
      stream.on('finish', resolve);
      superagent.get(image.url).pipe(stream);
    })))
    console.log('URLS done downloading')
  
    await browser.close();
  };

  downloadGallery = async (vin) => {
    var galleryUrls = [];
    async function ensureCarouselVisible() {
        var imgWrap;
        do {
            imgWrap = document.elementFromPoint(100, 100);
            console.log(imgWrap.classList);
            await delay(50);
        } while(imgWrap.classList.contains('pswp__img--placeholder'));
        
      }
      
      function delay(ms) {
        return new Promise((resolve) => setTimeout(resolve, ms));
      }
      
      // Find the active image, surround it in an anchor tag, then click it.
      async function downloadImage(id) {
        const imgWrap = document.elementFromPoint(300, 300);
        const children = imgWrap.querySelectorAll('.pswp__img');
        const img = children[children.length - 1];
        console.log(img, imgWrap);
        // debugger;
        // Full image hasn't loaded yet
        const src = imgWrap.src.split('?')[0]// get rid of querystring
        return downloadSrc(src, id);
      }
      
      function downloadSrc(src, id) {
        galleryUrls.push({
          fileName: id,
          url:src
        })
      }
      
      function nextImage() {
        document.querySelector('.pswp__button.pswp__button--arrow--right').click();
      }
      
      function getCounterValue() {
        const [position, total] = document.querySelector('.pswp__counter').textContent.split('/');
        return parseInt(position.trim(), 10);
      }
      
      function run() {
        return new Promise(async (resolve, reject) => {
          await ensureCarouselVisible();
          await delay(500);
          const firstValue = getCounterValue();
          do {
            await downloadImage(`${vin}-${getCounterValue()}`);
            nextImage();
            await delay(100);
          } while(getCounterValue() !== firstValue);
          return resolve(galleryUrls)
        }) 
        
      }
      
      return new Promise((resolve, reject) => {
        run().then(resolve);
      });
  }

  run();